WEDNESDAY, Sept. 19 (HealthDay News) -- Physicians are less likely to trust even top-notch clinical research if it is funded by a pharmaceutical company, a new study suggests.

The researchers found that doctors downgraded their perception of research when told it was industry-funded, whether or not the studies were rigorously done or of high quality.

Although attention to potential sources of bias is important, such skepticism can reduce the acceptance of valuable new information critical to advancing health care, the researchers said.

"The issue is, it could be a problem if the findings of high-quality research aren't being implemented," said Dr. Aaron Kesselheim, lead author of the study and assistant professor of medicine at Harvard Medical School in Boston.

The study was published Sept. 20 in the New England Journal of Medicine.

Dr. Jeffrey Drazen, the journal's editor-in-chief and a professor of medicine at Harvard, said the validity of a research paper should be based solely on the quality of the research -- how the study was designed, conducted and analyzed -- not by the funding source. "Rigor eliminates bias," he said.

"One would think that the translation of research findings into clinical actions would depend solely on the importance of the research question and the quality of the data used to answer it, but this assumption is not entirely true," Drazen said in an editorial accompanying the research.

Pharmaceutical companies sponsor a large proportion of clinical trials
of new treatments, the researchers noted.

Over the past 10 years or so, any financial support by drug makers has been noted in papers published in most medical research publications, Drazen explained. Some journals even include disclosures in the published abstracts of the studies -- short summaries that are widely read.

Such disclosures have been based on the assumption that when industry has a financial stake in the outcome of research, the study results can be biased to favor the source of the financial support.

"There were a number of egregious examples of bad behavior in the past, widely reported in the press," Drazen said. "So some people immediately think, 'If it's a drug company there must be something hidden here.'"

Kesselheim said he and his co-authors set out to better understand the impact that the disclosures were having on physician interpretation and practice.

"We asked ourselves, What would be ideal? And we decided it would be good if physicians took these disclaimers into account in studies of poor quality, but maybe not with the strong studies," Kesselheim said. "We wondered if physicians would moderate their responses when disclaimers were present."

The researchers developed 27 abstracts describing hypothetical research studies looking at three made-up drugs for three diseases: diabetes, hyperlipidemia (high blood fat levels) and angina pectoris (chest pain due to a lack of oxygen to the heart).

They also randomly varied the funding sources. One abstract listed the U.S. National Institutes of Health as the sponsor, another listed a fictitious drug company and a third said there was no external source of support.

More than 500 randomly selected internists were given three abstracts to review. The internists answered questions about the evidence presented in the research and how willing they would be to prescribe the drug based on the study. The physicians put more faith in the best-done studies, and 54 percent perceived the level of study rigor accurately.

But disclosure of industry funding, as compared with no disclosure, led physicians to downgrade the rigor of a trial, decrease their confidence in the study results and reduce their willingness to prescribe the drugs.

Physicians were half as willing to prescribe drugs studied in industry-funded trials as they were to prescribe drugs evaluated in NIH-sponsored trials.

Kesselheim said he thinks it's reasonable to be skeptical of research but it's important to move beyond that skepticism when the message from the studies is clear.

To increase the confidence physicians have in research supported by drug companies, Kesselheim said pharmaceutical companies should make all the data they submit to the U.S. Food and Drug Administration transparent and accessible by the public. Currently, he said, the information is provided only in the form of a summary statement.

Drazen expressed concern for the people who join clinical trials. "It's so important to continue to participate in research regardless of who is supporting it," he said. "And physicians should know these people earn our respect and we owe them the courtesy of acting on the findings when the research is solid."